Polymers, particularly polyesters, are produced on a large scale by means of reactors in accordance with DE 695 20 087 [U.S. Pat. No. 5,599,507] or DE OS 19 59 139 [U.S. Pat. No. 3,630,688]. Reactors of that kind are usually charged with low-viscosity to medium-viscosity starting substances with viscosities up to 10 Pas. Cages having stirring elements are provided in these known reactors. According to DE OS 19 59 139 the reactor additionally has two central shafts that carry the rotary cages.
If polymers or polyesters are to be produced in smaller quantities of, for example, only up to 2,000 kg/h and the starting substances in specific circumstances are also already of higher viscosity, for example with viscosities of approximately 100 Pas or even above that, then these reactors cannot be simply reduced to whatever size in order to still obtain polyesters of high quality. Added to that is the fact that high-power motors and large amounts of energy are needed for drive of the cages.
DE 198 11 280 [U.S. Pat. No. 6,162,837] in fact discloses a apparatus for recovery of linear polyester, in which high-viscosity starting materials can be used, but this apparatus, too, is complicated and has a space-consuming and energy-consuming construction.
U.S. Pat. No. 8,796,401 discloses a reactor that has stirring elements and conveying elements. However, this reactor has neither a vent for discharge of gases nor an intake extruder that is connected with the reactor by a common shaft and common drive. This reactor also serves for large-scale production of high-viscosity polymer materials.
DD 57 700 A5 discloses a method for producing polymerization and polycondensation products in which reactors of complicated construction are used. Apart from a charging chamber, a number of reaction chambers is provided here that makes the plant costly and that is not suitable for use for producing smaller amounts of polymers or polyesters.
In addition, US 2011/0105716 A1 discloses a serial arrangement of extruders and reactors that operate separately from one another and that are very complicated and costly. Use for production of smaller amounts of polymers or polyesters is not economically possible with plant of that kind.
DE 103 22 830 [U.S. Pat. No. 7,297,535] discloses a reactor for continuous polymerization of vinylmonomers as well as vinylpolymers. This reactor is constructed as a planetary roller extruder and manages entirely without an intake extruder.
If polymers, preferably polyesters, are to be produced in smaller quantities, the extruder for recovery of plastics material melts according to EP 1 434 680 [U.S. Pat. No. 7,513,677] has already proved satisfactory. Here, an intake extruder and a discharge extruder with a multi-worm extruder component are combined. Polycondensation or polymerization takes place in the multi-worm extruder component. However, the multi-worm extruder component still cannot be set in optimum manner particularly with respect to the processing conditions for polycondensation or polymerization that arise.